To meet the demand for wireless data traffic having increased since deployment of 4G (4th-Generation) communication systems, efforts have been made to develop an improved 5G (5th-Generation) or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘beyond 4G network’ or a ‘post LTE system’.
The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems.
In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, coordinated multi-points (CoMP), reception-end interference cancellation and the like.
In the 5G system, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
In order to perform Device-to-Device (D2D) communication (also known as direct communication), a User Equipment (UE) desiring to perform D2D communication may perform a D2D discovery process for determining whether another UE of its interest (or another D2D-enabled UE) is in proximity thereto.
A D2D UE (hereinafter, referred to as a ‘discovering UE’) performs the D2D discovery process to discover another D2D UE of its interest in its proximity. For example, a social networking application in a D2D UE may use the D2D discovery process. The D2D discovery may include an operation of enabling the user that uses the social networking application to discover a D2D UE among the UEs of users registered as his/her friends, using his/her D2D UE. The D2D discovery may also include an operation in which a D2D UE of the user that uses the social networking application is discovered even by each of the UEs of the users registered as his/her friends.
As another example, in the case of a discovery application, the D2D discovery may include an operation of discovering, for example, stores/restaurants and the like of its interest in its proximity depending on the user's purpose, using a discovering UE of a given user. The discovery information transmitted through the D2D discovery of the discovering UE may provide one or more of the following objects.
One of the above objects is to enable a user of a D2D application to discover another user having the same interest as his/her own interest within the possible D2D communication distance, using the discovering UE. Herein, the interest may include information about the interests (for example, specific movies, specific places, specific events and specific things) and/or specific user that the user currently desires to search for.
If another user having the same interest is obtained or discovered through the D2D discovery, a discovering UE may establish a dedicated connection for D2D communication with the D2D UE of another user. In order to establish the dedicated connection, the discovering UE should page a UE of discovered another user.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.